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本文在斜轧成型生产实践的基础上,将运动中的轧件与轧辊的相互关系抽象为曲面族和包络面的问题,然而用求包络面的方法导出了在已知轧件曲面的轴向剖线时辊形曲面方程的通用公式,并编制了通用计算程序,可以方便地计算轧辊曲面的轴向剖线、“法向”剖线等的精确尺寸。并可进一步计算用范成法磨削轧辊时的理论误差,以及调整轧辊角度时的理论误差。同时还可以由本文所导出的一般公式,方便地求出钢管矫直机辊形曲面方程以及它与钢管的接触线方程。 相似文献
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利用四辊轧机对酸洗后带钢进行了冷轧实验, 采用扫描电子显微镜对试样冷轧前后的表面形貌进行了跟踪观察, 采用TR200型粗糙度测量仪测试了轧制前后试样的表面粗糙度轮廓曲线, 研究了不同轧辊表面状态和摩擦条件下冷轧带钢表面形貌的演变规律。结果表明: 轧件表面形貌主要取决于表面凹坑和辊痕的尺寸, 随轧辊表面粗糙度的减小和轧制道次的增加, 轧件与轧辊表面的实际接触面积增加, 轧件表面凹坑和辊痕的尺寸均减小, 轧件表面光洁度提高; 当轧辊辊面粗糙度相同时, 采用油润滑轧制的试样表面光洁度比干摩擦轧制的试样表面光洁度高; 冷轧前几个道次轧辊的表面状态对最终成品带钢的表面形貌同样起着重要作用。 相似文献
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基于MDT的轧辊几何设计 总被引:2,自引:2,他引:0
讨论了借助于MDT的NURBS曲面造型功能进行轧辊几何设计的方法,建立了生成轧辊辊形和轧辊与轧件接触线的三维几何模型,并给出了设计实例。 相似文献
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本文根据空间解析几何理论,建立了二辊斜轧穿孔时的轧辊辊面方程,继而利用平截面法描绘了轧件与轧辊接触迹线的形状及其随送进角变化的性质。 相似文献
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采用刚塑性有限元法,以大型有限元软件DEFORM-3D为分析工具,考虑界面接触传热,对铜包铝复合电力扁排热轧成形过程进行了三维温度场模拟.结果表明:在轧件开始咬入与轧辊接触后,纯铜表面中部的温度先降低后升高,由于纯铜与轧辊的接触传热,轧辊与纯铜的接触部分温度低于铜包铝扁排侧部金属的温度;由于接触摩擦与塑性变形功转化为热量,开始轧制后轧件表面温度有所升高;轧制后铜包铝排铜层表面和铝芯的边部温度高于中部温度,由表及里温度升高;随着压下率的增大,在变形区轧件温度升高幅度增大;随着轧制速度的提高,在变形区铜层和铝芯温度变化更为剧烈,轧制后温降速率减小. 相似文献
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1 温度场与热应力场的计算在轧制过程中,热量不断由轧件传给轧辊,其上任一点由于同轧件与冷却水相接触而交替地被加热与冷却,因而引起交变热应力,使轧辊表面经受热疲劳作用,而在辊面形成表面径向裂纹。为了计算由此产生的热应力,必须预先计算辊内温度场的分布。轧辊内非定常温度场的分布,文中采用下式给出: 相似文献
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The deflection of rolls of Sendzimir mill with double AS-U-Roll was simulated by finite element method(FEM). The influences of rolling pressure, strip width and rolls-assignment on rolls deflection were analyzed. The results show that the work roll deflection increases with the increase of rolling pressure and the reduction of work roll radius, but the rigid displacement of work roll slightly changes; the work roll end might appear negative displacement for the narrow strip width and high rolling pressure that might cause the contact of work rolls. The research results are significant for guiding production and theoretical analysis of the rolls system of Sendzimir mill. 相似文献
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借助非线性有限元软件Marc,采用弹塑性有限元方法对十八辊轧机辊系进行了模拟,计算模型对辊系的弹性变形与带钢的弹塑性变形按照接触问题进行耦合分析。利用此模型,得出了轧制力对辊系弯曲变形的影响以及辊系弯曲变形沿轧件宽度方向的分布,并分析了轧机工作辊的不同方向弯曲变形情况,由对计算结果的分析可以为该轧机的辊系设计提供理论依据。 相似文献
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为了快速计算六辊冷轧机辊系的弹性变形,提出了一种新的辊系弹性变形算法。该算法直接采用数值法计算轧辊挠曲,避免了复杂的公式推导,简化了计算过程;在辊系协调变形的迭代计算过程中,内层迭代首次引入辊间中心点处压扁和辊间压扁区倾斜两个迭代调节量,建立了与辊间接触合力和接触区的总力矩的联系,外层迭代通过不断修正辊间相对压扁量增量循环迭代辊间接触力与轧辊挠曲,实现了整个辊系变形的快速协调。通过与国外计算结果比较和算例的验证,证明其有好的计算精度、收敛性和快速性,能离线指导新轧机工艺方案设计,具备板形在线设定计算应用的可能。 相似文献
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1 INTRODUCTIONItisnecessarytoevaluateperformance ,toana lyzeandtoestimatethemechanicalbehaviorofHCmillforusingitefficiently ,masteringthecharacteris ticofthe pressuretransversedistributionbetweenrolls,anddecreasingtherollsattritionwear.Largescalestudyonde… 相似文献
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<正> 长期以来,Mannesmann二辊穿孔机都用桶形轧辊,它的子午线是折直线,所以叫折线轧辊似较确切,虽然各国都在改进辊形,特别是大角度穿孔时的辊形,但从数学上来看,还是折(直)线形,无本质上的变化。 为了发展我国钢管制造技术,我们从1975年起研究折线轧辊下的变形区,给出它的曲面方程式和子午线方程式,证明了变形区是非线性的。 苏联乌克兰科学院EMeЛbяHeкO院士和ΦoMичeB研究折线轧辊下的轧辊开度 相似文献
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Numerical and experimental analysis of the dynamic effects in compact cluster mills for cold rolling
Prevention of dynamic instability caused by chatter phenomenon may be difficult in case of the so-called “cluster mill” because of the number of back-up rolls used to avoid bending of the work roll. A numerical simulation of the dynamics of the cluster mill may help to prevent the strip defects and to predict the life of bearings and rolls. Analytical models proposed in the literature for the two- and four-high mills are unfortunately inapplicable. This paper investigates whether the multi-body dynamics approach can be effective in analysing the so-called “Z-Mill”. Service monitoring detected in a real case some clear and dark bands on the strip surface, which disappeared after a calibration of rolls position. A numerical model was built by assuming that the mill stand and the strip could be analysed separately. Validation allowed concluding that modelling is effective, if relevant parameters are tuned on the experimental evidences. In particular damping and friction coefficients look the most critical to predict the actual value of rolling force. Mechanical nonlinearities introduced by the contact among rolls and by bearings increase the computational effort, but their role is somewhere overestimated in the literature. In practice, the multi-body dynamics approach still shows some limits, but they should be overcome, if a deeper experimental validation will be performed on a dedicated test rig, suitably designed to be largely instrumented. 相似文献
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Y. Saito T. Watanabe H. Utsunomiya 《Journal of Materials Engineering and Performance》1992,1(6):789-795
A new type of compact continuous mill called the “Satellite mill” has been developed to produce profiled metal strip from
flat strip. This mill consists of one large-diameter driven roll (central roll) and five smaller rolls (satellite rolls) arranged
along the periphery of the central roll. A strip is continuously rolled at five gaps between the central roll and the satellite
rolls. All rolls are driven at an equal roll peripheral speed to promote transverse metal flow or lateral spread. Guide shoes
are provided between the adjacent satellite rolls and are supported with two adjacent satellite rolls. They prevent a strip
from bulging or buckling. A test mill was constructed, and rolling experiments have been performed on the production of T-shaped
or U-shaped profiled aluminum strip. The deformation- load characteristics were investigated and compared with those of conventional
rolling. As a result, in the satellite mill rolling operation, elongation was suppressed. Lateral spread was enhanced, and
the profile of the product cross section was significantly improved. Consequently, the new rolling process was found to be
forming of profiled metal strip. 相似文献